Structure and method for a superbarrier to prevent diffusion between a noble and a non-noble metal

ABSTRACT

This invention relates generally to structure and method for preventing metal diffusion between a noble metal layer and an adjoining non-noble metal layer, and more specifically to new structures and methods for providing a superbarrier structure between copper and an adjoining noble metal layer. This is achieved by sequentially deposited a layer of non-noble metal, a layer of titanium, a layer of molybdenum, and a layer of noble or relatively less noble metal as the interconnecting metallurgy. This invention also relates to an improved multilayer metallurgical pad or metallurgical structure for mating at least a portion of a pin or a connector or a wire to a substrate.

FIELD OF THE INVENTION

This invention relates generally to structure and method for preventingmetal diffusion between a noble metal layer and an adjoining non-noblemetal layer, and more specifically to new structures and methods forproviding a superbarrier structure between copper and an adjoining noblemetal layer. This is achieved by sequentially depositing on the layer ofnon-noble metal, a layer of titanium, a layer of molybdenum, and a layerof noble or relatively less noble metal as the interconnectingmetallurgy. This invention also relates to an improved multilayermetallurgical pad or metallurgical structure for mating at least aportion of a pin or a connector or a wire to a substrate.

BACKGROUND OF THE INVENTION

On one of the surfaces of a semiconductor component, such as a chip,there is an arrangement of pads, each with a solder ball (hereinafterreferred to as C-4 solder ball pads or just C-4s) which are adapted toprovide connection between the chip and a substrate, such as a ceramicsubstrate. This is done by means of bonding of the solder balls whichare heated to a temperature above the melting temperature of the solderballs thereby permitting solder bonding of the solder balls to padscarried on the mating surface of the substrate. Connected between thesolder pad areas and other sites on or in the substrate are so-calledfan-out lines which extend along the mating surface of the substratebeneath a layer of insulation. At certain locations on the surface ofthe substrate, it is necessary to make pads available for engineeringchange (EC) wiring to be connected to the fan-out metallurgy. Theengineering change wiring, however, is usually connected to the pads bythe process of wire bonding, either by ultrasonic vibration or bythermo-compression techniques, or by solder bonding. The metallurgicalrequirements for solder bonding as contrasted with the requirements forwire bonding techniques differ.

Bi-metallic layers have been used for different purposes, for example,Ashley (U.S. Pat. No. 2,847,331) discloses a hydrogen isotope targetdisc consisting of a backing of molybdenum or tungsten having a coatingof titanium on the backing.

Similarly, Rostoker et al. (U.S. Pat. No. 3,060,557) disclosed a methodin which intermediate metals are interposed between a base metal and acladding metal, such interposed material acts as a diffusion barrier toeliminate the formation of brittle and continuous intermetalliccompounds between the base and the cladding metal.

Nurnberg et al. (U.S. Pat. No. 3,633,076) disclosed a method of applyinga metallic contact strip to a semiconductor, where the contact stripconsisted of three sequential layers of different metals stacked uponeach other. The lowest or inner layer is supposed to possess a highaffinity towards oxygen, while the middle layer is preferably selectedfrom molybdenum, tungsten, vanadium and chromium, and the outer layer isa noble metal.

In Bhattacharya et al. (U.S. Pat. 4,463,059) the metallurgicalrequirements for solder bonding and wire bonding were discussed in thecontext of the top surface metallurgy of a ceramic substrate. Severalmetallurgical structures were proposed. For solder bonding, one proposedstructure consisted of fan-out lines of chromium and gold, then abarrier layer of cobalt or chromium over the gold followed by a toplayer of nickel or copper. For wire bonding, the nickel or copper toplayer was eliminated. In other structures, Bhattacharya et al. suggestedthe use of gold where solder bonding was to occur.

Merrin et al. (U.S. Pat. Re. No. 27,934) discussed the requirements ofball limiting metallurgy (BLM), i.e., the pads on the bottom of the chipwhich serve to limit the flow of the solder balls upon heating. Theparticular ball limiting metallurgy proposed by Merrin et al. comprisessequential layers of chromium, copper and then gold.

Similarly, Research Disclosure 26726, Number 267, (July 1986), disclosesa backside preparation and metallization of silicon wafers fordie-bonding comprising coating the backside of a semiconductor chip withsequential layers of chromium or titanium, nickel or copper followed bya top layer of gold, and which is followed by a coating of tin.

Mace et al. (U.S. Pat. No. 4,772,523) discloses a compositemetallization structure on a glass substrate consisting ofCr/Au/Ni/Au/solder layers for a silicon capacitive pressure sensor. Theinterior gold layer does not bond strongly to chromium because of a lackof mutual solubility, but it appears that the interior gold layer willdiffuse into the grain boundaries of the nickel and chrome metallizationlayer during the anodic bonding process. This anodic bonding process isdone prior to the solder application, and the composite metallizationlayers are subjected to anodic-bonding temperatures under an electricpotential to diffuse gold into nickel and chromium.

In Agarwala et al. (U.S. Pat. No. 4,985,310) a cobalt layer is disclosedas a diffusion barrier between a noble metal (Au, Pt, Pd, Sn) and a lessnoble metal (Cu, Ti, Cr) for use in soldering and wire bonding pads inelectronic components.

The present day top surface metallurgy for ceramic substrates maycomprise a multilayered metallurgical structure of chromium or titanium,copper and then gold or, alternatively, molybdenum, nickel and thengold. The currently favored ball limiting metallurgy comprises chromium,copper and gold. Both the top surface metallurgy (hereinafter TSM) andthe ball limiting metallurgy (hereinafter BLM) undergo many solderreflow operations during the process of joining the chips to the ceramicsubstrate. The gold in the TSM and BLM quickly dissolves in the solder,leaving the underlying copper (or nickel) to react with the solder whichis usually of a lead/tin composition. The solder and the underlyingcopper (or nickel) have been chosen because they form a good solderjoint.

The reaction of the copper and the solder, however, causes the formationof copper/tin intermetallics. Ordinarily, this would not be a problembut due to the multiple solder reflows necessary to join the chips tothe ceramic substrate, the copper/tin intermetallics, eventually buildup to the point where they spall off the underlying metallization,resulting in the loss of BLM conduction as well as the loss of areaction barrier between the solder and the underlying chipmetallization. Further, the spalling of these intermetallics can lead toearly failure of the solder joint.

Although cobalt serves well as a reaction barrier to solder it does notlimit the outward diffusion of copper to the top surface of noble metalsin oxidizing gas ambient commonly encountered in component assemblyprocesses and service environments of electronic assemblies. This outdiffusion renders the noble metal surface unbondable by wires and leadsto high contact resistances in pad-on-pad contact structures.

PURPOSES AND SUMMARY OF THE INVENTION

It is a purpose of the invention to have an improved joint betweenelectronic components which is not as susceptible to excessive formationof intermetallics and their accompanying problems.

It is another purpose of the invention to have an improved joint betweenelectronic components comprising a metallurgical structure which has areduced rate of reaction with solder and braze alloys.

It is yet another purpose of the invention to have an improved jointbetween electronic components after multiple solder reflows.

Still another purpose of this invention is to provide an interconnectingmetallurgy which provides:

(a) low enough stresses, that the substrate does not crack,

(b) is sufficiently noble, so that corrosion in field environment doesnot cause intolerable fails,

(c) adheres to the substrate, such that, it will not separate under theprocess and field stresses, and

(d) be wettable by braze and solder, and must react with them to form astrong metallurgical bond by solid solution and/or intermetallicsformation.

According to one aspect of the invention there is disclosed amultilayered interconnecting metallurgical structure for an electroniccomponent comprising, a structure over a substrate, wherein saidstructure comprises sequentially formed layers of at least one adhesionlayer, at least one non-noble metal layer, a titanium layer, amolybdenum layer and at least one noble or relatively less noble metallayer.

According to another aspect of the invention, there is disclosed amethod for forming a multilayered interconnecting metallurgicalstructure for an electronic component comprising the steps of:

a) depositing at least one electrically conductive adhesion layerdirectly on said electronic component,

b) depositing at least one non-noble metal layer directly on said atleast one electrically conductive adhesion layer,

c) depositing a layer of titanium on said layer of non-noble metallayer,

d) depositing a layer of molybdenum directly on said layer of titanium,and

e) depositing at least one layer of noble or relatively less noble metaldirectly on said layer of titanium, thereby forming said multilayeredinterconnecting metallurgical structure.

These and other purposes and aspects of the invention will become moreapparent after referring to the following description considered inconjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The features of the invention believed to be novel and the elementscharacteristic of the invention are set forth with particularity in theappended claims. The figures are for illustration purposes only and arenot drawn to scale. The invention itself, however, both as toorganization and method of operation, may best be understood byreference to the detailed description which follows taken in conjunctionwith the accompanying drawings in which:

FIG. 1 is a cross-sectional view of a multilayered metallurgicalstructure according to one aspect of the invention.

FIG. 2 shows a pin connected to the multilayered metallurgical structureof FIG. 1.

FIG. 3 shows a wire connected to the multilayered metallurgicalstructure of FIG. 1.

FIG. 4 is another embodiment of the invention where a connector havingmetal pads is being secured to a substrate which has the multilayeredmetallurgical structure of this invention.

FIG. 5 is yet another embodiment of the invention where an edgeconnector is secured to a substrate having multilayered metallurgicaledge connection.

DETAILED DESCRIPTION OF THE INVENTION

Preferred embodiments of the present invention are depicted in FIGS.1-5, in which like numerals refer to like features of the invention.Such features are not necessarily shown to scale in the drawings.

In film connectors and edge connectors, which rely on pressure contact,the oxidation at the contact is of utmost importance because itincreases the electric resistance and can cause electric failures. Tocombat oxidation the contact films at the surface are made of a noblemetal, such as gold. However, underlying base metals, i.e., copper,nickel, cobalt, etc., can diffuse into the noble metal surface andoxidize during the thermal cycling, such as during polymer curing cycle,chip joining, pin brazing and also under field conditions during thelifetime of the part or module. Therefore, the diffusion barriers ofthis invention are needed to prevent the diffusion of such undesiredelements in the gold or noble metal surface.

It has been discovered that a Mo/Ti bi-metallic barrier layer between anoble or relatively less noble metal and a non-noble metal preventsdiffusion of atoms from the non-noble metal layer to the noble metallayer and also from the bi-metallic barrier layer itself. For the easeof discussion both the noble and relatively less noble metals will bereferred to as noble metals.

The use of either Mo (molybdenum) or Ti (titanium) alone has shown notto work. Because, Mo is not a good barrier to the non-noble metal, butit will not diffuse into the noble metal. While, Ti is a good barrier tothe non-noble metal, but it will itself diffuse into the noble metal.However, it has been discovered that both in combination do not diffuseeither themselves into the noble metal or allow any other metal on theopposite side to diffuse into the noble or relatively less noble metal.

This is accomplished by insuring that Mo layer always contacts the nobleor relatively less noble metal layer, and that titanium layer alwayscontacts the non-noble metal layer. This arrangement has workedextremely well for noble or relatively less noble metals, such as, Ag,Au, Pd, Pt, etc., and non-noble metals, such as, aluminum, copper, etc.,and especially in an annealing atmosphere encountered in electronicapplications.

The main purpose of this bi-metallic diffusion barrier layer is toprevent the non-noble underlayer from diffusing into the noble orrelatively less noble metal layer, and then oxidize the noble orrelative less noble metal layer and degrade the contact resistance ofthe noble metal layer.

Noble metals provide very low contact resistance but they are veryexpensive, therefore, a non-noble metal layer in combination with thenoble metal layer is used in applications where otherwise only noblemetals would be desired.

The bi-metallic barrier layer of Ti/Mo between the non-noble metal layerand the noble metal layer according to this invention reduces thestress, almost eliminates corrosion, provides a very good TCE (ThermalCoefficient of Expansion), and there is no pull-strength degradation.This invention can be used with any type of single or multilayersubstrates, for example, the substrates could be selected from a groupcomprising, ceramic substrates, silicon substrates, glass-ceramicsubstrates, alumina substrates, aluminum nitride substrates, siliconnitride substrates, mullite substrates, etc.

Any surface mountable item, such as pins, flexible connector, pad-on-padconnector can also be successfully connected to this new metallurgy.

This new metallurgy can also be used for edge connector applications asillustrated in FIG. 5.

Referring to the Figures in more detail and particularly referring toFIG. 1, there is shown a multilayered metallurgical structure or pad,generally indicated by 30, for an electronic component, 12. Theelectronic component 12, can be a silicon device, such as asemiconductor chip, or a substrate, such as a ceramic substrate. For theease of understanding this invention the electronic component 12, willhereinafter be referred to as substrate 12. The substrate or electroniccomponent 12, has at least one via connection 14. On one of the surfacesof the substrate 12, can be a layer of wiring metallurgy (not shown). Byway of illustration and not limitation, the wiring metallurgy may be analuminum/copper alloy, aluminum, copper, gold, or any suitableelectrically conductive material. The multilayer metallurgical structure30, can be a ball limiting metallurgy (BLM), pin braze pad, C4 pad, wirebond pad, etc.

FIG. 1, shows the basic metal film structure deposited on the substrate12. The layers or films are deposited sequentially within a vacuumsystem (without breaking the vacuum) by chemical vapor deposition,etching, evaporation, sputtering, or by any other suitable technique. Anelectrically conductive adhesion layer 15, is first deposited directlyon the substrate 12, so that it is electrically in contact with at leasta portion of at least one via connection 14. In some cases the adhesionlayer 15, may have to contact two or more via connections 14. This isfollowed by a layer of non-noble metal 16, and a layer of titanium 17,deposited directly on the layer of non-noble metal 16. Next a layer ofmolybdenum 18, is deposited over the layer of titanium 17, and, finally,a layer of noble or relatively less noble metal layer 20, is depositedon the molybdenum layer 18. These deposited layers are then typicallyformed into an array of pads. These pads can now be used to connectvarious components such as wires, pins, connectors etc.

Within the substrate 12, there are one or more via connections 14, forcommunicating between the wiring in the various layers (not shown) ofthe substrate 12, and other electronic components that may be joined tothe substrate 12.

The particular application will determine the variation and/or thethickness of the metallurgy that is most suitable and economical forforming the multilayered metallurgical structure 30, such as a pad.

It should be understood that noble or relatively less noble metal, andhereinafter referred to as noble metal, means those metals and alloysthat have a reduced tendency to oxidize in air. Included within thisdefinition are true noble metals such as gold, platinum, palladium andalloys thereof, and also other metals having a reduced tendency tooxidize in air such as tin. The noble or relatively less noble metal isselected from the group consisting of gold, palladium, platinum,rhodium, silver, tin and mixtures thereof. The use of the term noblemetal shall hereinafter encompass noble as well as relatively less noblemetals.

A non-noble metal is defined as a metal which has a tendency to oxidizein air. The non-noble metal layer is selected from a group comprisingaluminum, cobalt, copper, nickel, to name a few, and mixtures thereof.

The electrically conductive adhesion layer is selected from a groupcomprising chromium, molybdenum, tantalum, titanium, tungsten,zirconium, vanadium, hafnium, to name a few, and mixtures thereof.

It is preferred that the noble or relatively less noble metal layer 20,be gold, but alternatively could also be platinum, palladium, rhodium ortin. Similarly, it is preferred that the non-noble metal layer 16, iscopper, but alternatively could also be aluminum, cobalt, nickel, toname a few, and mixtures thereof.

It is further preferred that the adhesion layer 15, has a thickness fromabout 0.02 to about 0.10 micron, and preferably between about 0.02 toabout 0.03 micron, the non-noble metal layer 16, has a thickness fromabout 1.00 to about 8.00 micron, and preferably between about 2.0 toabout 6.0 micron, the titanium layer 17, has a thickness from about 0.20to about 2.00 micron, and preferably between about 0.50 to about 1.50micron, the molybdenum layer 18, has a thickness from about 0.20 toabout 2.00 micron, and preferably between about 0.50 to about 1.50micron, and the noble or relatively less noble metal layer 20, has athickness from about 0.5 to about 5.00 micron, and preferably betweenabout 1.00 to about 5.00 micron.

The non-noble metal layer 16, is there to provide electricaldistribution over the substrate 12. The bi-metallic layer of titanium17, and molybdenum 18, is there as a superbarrier between the noblemetal layer 20, and the non-noble metal layer 16. This combination oflayers provide high resistance to corrosion and chemical compatibilityand solubility with the other metals, which is a key requirement formost applications. The noble metal layer 20, such as gold, is to protectthe surface and preserve the wettability of the braze/solder, and tomake possible wire bonding by ultrasonics, pressure bonding,microwelding, etc., and also to provide intimate contact for thepad-on-pad and edge connectors.

The multilayered metallurgical pad 30, that is formed may serve thepurpose of a pad for joining with a pin 24, using solder or braze 22, asshown in FIG. At least a portion of the noble or relatively less noblemetal layer is in contact with a solder material. The structure shown inFIG. 2, may be formed in a number of ways, but one particular way is tofirst deposit a layer of insulating material (not shown), for example, apolyimide, over the substrate 12, as described in Boss et al., U.S. Pat.No. 4,880,684, the disclosure of which is incorporated herein byreference. By photolithography, or etching or laser ablation thepolyimide is removed in the area over via 14, fully exposing themetallurgy of the via Thereafter, the multilayer metallurgical structureor pad 30, is deposited as discussed earlier. The multilayeredmetallurgy that is deposited over the at least one via 14, is similar tothe structure shown in FIG. 1. After the deposition of the adhesionlayer 15, over at least one via a non-noble metal layer 16, such ascopper, is deposited on the adhesion layer 15, followed by a layer oftitanium 17, and a layer of molybdenum 18, and finally a layer of nobleor relatively less noble metal 20, preferably gold, which is depositeddirectly on the layer of molybdenum 18. The pin 24, is then secured tothe solder or braze 22, as disclosed by methods well known in the art,such as U.S. Pat. No. 4,970,570 (Agarwala, et al), the disclosure ofwhich is incorporated herein by reference.

If a solder ball (not shown) is used to secure to the solder 22, insteadof the pin 24, then the multilayer metallurgical structure 30, andsubstrate 12, are heated to cause the solder 22, to melt and flow astaught by the Merrin et al, U.S. Pat. Re. No. 27,934.

In practice if the multilayer metallurgical structure or pad 30, was tocome in contact with solder, the noble metal layer 20, would dissolveinto the solder during the reflow operation. Accordingly, the noblemetal layer 20, would be fugitive. On the other hand, if the multilayermetallurgical structure 30, was only to undergo wire bonding, wheresoldering was not to occur, then noble metal layer 20, would remainsubstantially in place.

An unexpected advantage of the noble metal layer 20, is that the noblemetal forms a thin layer of intermetallic that is adherent with thebraze or solder 22, and the underlying molybdenum layer 18. Duringreflow and rework operations, this intermetallic remains wettable by thesolder so that fluxing is not required.

During the reflow operation, the noble metal layer 20, becomes absorbedwithin the solder 22, and thus is considered to be a fugitive layer. Theimportance of the noble metal layer resides in the fact that it preventsthe underlying molybdenum layer from oxidizing during storage, andtherefore allowing it to wet and react with the solder.

Alternatively, the multilayer metallurgical pad may serve the purpose ofa wire bonding site for an engineering change pad in which case the TSMmay not come in contact with solder. For example, wire bonding may bedone by ultrasonic vibration or thermo-compression, in which case,solder is not used.

An example of the application of the pad as a wire-bonding site is shownin FIG. 3. Here at least a portion of the wire 26, is attached to atleast a portion of the pad structure 30, (shown in FIG. 1) by thebonding technique which is most suitable for the application, such asultrasonics, pressure bonding, microweld, etc. This bonding will resultin a diffusion zone 28.

The thickness of the noble metal layer 20, such as gold, will varydepending on the bonding technique employed, i.e., for ultrasonicbonding, thick gold would be required. Because of the wire 26, largerthermal expansion coefficient relative to the substrate 12, high shearstresses are induced to the metals and metal/substrate interface andouter boundaries. Again, especially for microwelding, non-noble metallayer provide both the adhesion and stress reduction, gold the bondingcapacity, and molybdenum and titanium the reaction control.

As illustrated so far, the multilayer metallurgical structure of thisinvention has the required properties of low stress, minimal corrosion,strong adhesion to the substrate (ceramics, polymers, etc.) andreactability with brazes and solders in a wide range of applications.Each layer is there for a specific purpose.

There may be applications in which the substrate is very brittle andsusceptible to cracking, in which case the multilayer metallurgicalstructure may be too stressful if deposited directly on the substrate.In such a case, a polymeric film, i.e. polyimide, can be depositeddirectly on the substrate and a portion of this polymeric film isablated to provide an electrical contact between the via and theoverlaying metallurgy. This polymeric film on the substrate acts as acushion to absorb most of the film and/or braze induced stress,preventing their transmission to the substrate.

The structure of this invention can be on a base metallurgy, (not shown)wherein the base metallurgy is between the adhesion layer 15, and thenon-noble metal layer 16, and, wherein the material for the basemetallurgy is selected from the group consisting of aluminum, chromium,cobalt, copper, hafnium, molybdenum nickel, niobium, tantalum, titanium,zirconium, noble metals and mixtures thereof.

Another application of this invention is illustrated in FIG. 4, which isan example of pad-on-pad connector. A rigid or flexible connector 45,having metal pads 47, is made to contact the substrate 12, havingstructure 30, such as a pad 30. In most situations the metal pads 47,have a corresponding structure 30, such as a pad 30, and vice versa. Nometallurgical bond between the two pad surfaces is formed, i.e., betweenpads 47, and pad 30. The electrical contact between the pads 30 and 47,is maintained under adequate pressure, achieved through the flexibilityof the connector or individual pads. The pad surfaces that come inphysical contact must be noble so that oxidation does not occur, whichwould eventually produce high unacceptable electric contact-resistance.The connectors can be pad-on-pad, edge connectors or other types, allrequiring mechanical and corrosion stability provided by the disclosedmetallurgy. The mechanical aspect can be severe because connectors areoften flat flexible cables constructed of polymeric and metallic layeredcomposite structures (e.g., Kapton/Cu), which have relatively highthermal expansion coefficients compared to the ceramic substrates andwhich induce high shear stresses to the connecting pads.

An example of using the multilayered metallurgical interconnection ofthis invention as an edge connector is illustrated in FIG. 5. By methodswell known in the art the substrate 12, has edge pads 55, formed on theedges of the substrate 12. The edge pad 55, could have the multilayeredmetallurgy of pad 30.

In FIG. 5, the multilayered metallurgy of pad 30, is shown, where theedge pad 55, is comprised of sequentially deposited layers of at leastone adhesion layer 59, at least one non-noble metal layer 56, a titaniumlayer 57, a molybdenum layer 58, and at least one layer of noble metal60. Preferably, the non-noble metal layer 56, is copper, and the noblemetal layer 60, is gold. An edge connector 50, having extensions 51 and53, to accommodate springs 52 and 54, receives the edge of the substrate12, so that at least a portion of the pad 55, makes an electricalconnection with at least a portion of the edge connector 50.

The BLM metallurgy of this invention has shown extremely good results.The BLM that is currently used in some cases has been shown to be highlysusceptible to chlorine induced corrosion in repeated evaluations. Thisinvention has also changed the capture pad metallurgy, i.e., that oncethe I/O pad were removed as the weak link, the current capture pads alsoemerged as having corrosion related problems.

The change to a molybdenum based system for both the I/O and capturepads has given a metallurgy that is corrosion resistant with nodegradation in pull strengths.

This invention is applicable in arts such as processing where it can beemployed in manufacturing semiconductor products for personal computers,minicomputers, large scale computers and other data processingequipment. In particular, this process is applicable to the manufactureof VLSI chips for industrial and consumer electronic devices. Electronicproducts such as transportation and control systems incorporatingprocessing systems for continuous monitoring and like functions can useproducts made by use of this invention.

While the present invention has been particularly described, inconjunction with a specific preferred embodiment, it is evident thatmany alternatives, modifications and variations will be apparent tothose skilled in the art in light of the foregoing description. It istherefore contemplated that the appended claims will embrace any suchalternatives, modifications and variations as falling within the truescope and spirit of the present invention.

What is claimed is:
 1. A multilayered interconnecting metallurgical structure to prevent diffusion between at least one non-noble metal layer and at least one noble or relatively less noble metal layer for an electronic component comprising, a structure over a substrate, wherein said structure comprises sequentially formed layers of at least one electrically conductive metal adhesion layer, at least one non-noble metal layer, a titanium layer, a molybdenum layer and at least one noble or relatively less noble metal layer and wherein at least a portion of said at least one electrically conductive metal adhesion layer is in direct electrical contact with at least one via in said substrate and wherein the combination of said titanium layer and said molybdenum layer prevents diffusion between said at least one non-noble metal layer and said at least one noble or relatively less noble metal layer.
 2. The structure of claim 1, wherein said non-noble metal layer is on a base metallurgy and wherein said base metallurgy is selected from the group consisting of aluminum, chromium, cobalt, copper, hafnium, molybdenum nickel, niobium, tantalum, titanium, zirconium, noble metals and mixtures thereof.
 3. The structure of claim 1, wherein said non-noble metal layer is selected from the group consisting of aluminum, cobalt, copper, nickel and mixtures thereof.
 4. The structure of claim 1, wherein said noble or relatively less noble metal layer is selected from the group consisting of gold, platinum, palladium, rhodium, silver, tin and mixtures thereof.
 5. The structure of claim 1, wherein said substrate is a semiconductor chip.
 6. The structure of claim 1, wherein said substrate is selected from a group consisting of ceramic substrates, silicon substrates, glass-ceramic substrates, alumina substrates, aluminum nitride substrates, silicon nitride substrates or mullite substrates.
 7. The structure of claim 1, wherein at least a portion of said noble or relatively less noble metal layer is in contact with a solder material.
 8. The structure of claim 7, wherein a pin is secured to said solder material.
 9. The structure of claim 7, wherein a solder ball is secured to said solder material.
 10. The structure of claim 1, wherein at least a portion of a wire is secured to at least a portion of said noble or relatively less noble metal.
 11. The structure of claim 1, wherein at least a portion of a connector is in contact with at least a portion of said structure.
 12. The structure of claim 1, wherein said electrically conductive metal adhesion layer has a thickness from about 0.02 to about 0.10 micron, and preferably between about 0.02 to about 0.03 micron, said non-noble metal layer has a thickness from about 1.00 to about 8.00 micron, and preferably between about 2.00 to about 6.00 micron, said titanium layer has a thickness from about 0.20 to about 2.00 micron, and preferably between about 0.50 to about 1.50 micron, said molybdenum layer has a thickness from about 0.20 to about 2.00 micron, and preferably between about 0.50 to about 1.50 micron, and said noble or relatively less noble metal layer has a thickness from about 0.5 to about 5.00 micron, and preferably between about 1.00 to about 5.00 micron.
 13. The structure of claim 1, wherein said electrically conductive metal adhesion layer has a thickness from about 0.02 to about 0.10 micron, and preferably between about 0.02 to about 0.03 micron.
 14. The structure of claim 1, wherein said non-noble metal layer has a thickness from about 1.00 to about 8.00 micron, and preferably between about 2.00 to about 6.00 micron.
 15. The structure of claim 1, wherein said electrically conductive metal adhesion layer is selected from a group consisting of chromium, tantalum, titanium, tungsten, hafnium, molybdenum, vanadium, zirconium and mixtures thereof.
 16. The structure of claim 1, wherein said titanium layer has a thickness from about 0.02 to about 2.00 micron, and preferably between about 0.50 to about 1.50 micron.
 17. The structure of claim 1, wherein said molybdenum layer has a thickness from about 0.02 to about 2.00 micron, and preferably between about 0.50 to about 1.50 micron.
 18. The structure of claim 1, wherein said noble or relatively less noble metal layer has a thickness from about 0.5 to about 5.00 micron and preferably between about 1.00 to about 5.00 micron.
 19. The structure of claim 1, wherein said titanium layer has a thickness from about 0.02 to about 2.00 micron, and preferably between about 0.50 to about 1.50 micron, and wherein said molybdenum layer has a thickness from about 0.20 to about 2.00 micron, and preferably between about 0.50 to about 1.50 micron. 